In the Victor D. Molitor U.S. Pat. No. 4,125,148, the invention is exemplified by a hood or grease extraction ventilator provided with heat exchangers through which the hot gases pulled into the hood from above cooking equipment are utilized in heating a heat transfer liquid, which is then supplied to a heat exchanger for heating fresh makeup air. These same gases are then passed through a chilling device in which the now somewhat cool gases engage water, as in a water bath or through sprays, to cool the gases for discharge to the atmosphere, and also to chill the water through evaporation. This chilled water is then used alternatively for cooling purposes, such as to cool the same makeup air, while water initially contacting the heated gases may be passed through the heat exchanger to cool the gases prior to engaging the water to be chilled. The so cooled exhaust gases also produce a lesser pollution effect. Considerable savings can be effected by thus producing chilled water through use of exhaust gases passing through a grease extraction ventilator or hood, but such exhaust gases must still be exhausted to the atmosphere, since they are not suitable for introduction into rooms requiring treated air, because of cooking odors and the like. Also, the temperature to which such water may be chilled is limited by the dew point of the gases, which may contain a substantial amount of moisture, such as produced by cooking.
For a considerable time, in the past, so-called "swamp coolers", which are essentially devices for cooling air by passing air into contact with water to produce evaporation, had been used to cool incoming air on warm days. However, in climates in which the humidity is relatively high, the amount of cooling which may be produced is again limited by the dew point of the incoming fresh air, while the initial high humidity tends to be increased by moisture picked up through engagement with the water. Thus, in sections of the country in which the humidity may become relatively high during the summer months, the so-called "swamp cooler" has fallen into disfavor and has been replaced by mechanical refrigeration equipment which does not add to the humidity of the air cooled.
Among the objects of this invention are to provide a method of and apparatus for supplying treated air to separate spaces having different treated air requirements, wherein a second space requires additional cooling; to provide such a method and apparatus which can operate efficiently and effectively to produce cooled air for a space having additional cooling requirements; to provide such a method and apparatus which involves the use of previously treated air whose humidity is normally not as high as outside air; to provide such a method and apparatus by which cool air may be supplied to a space in which excessive heat is a problem, such as due to cooking equipment in a cooking space; to provide such a method and apparatus which not only provides adequate cooling for the space in which excess heat is a problem, but also will provide water chilled to a temperature which can be effectively utilized in cooling other air, such as fresh makeup air from the outside; to provide such a method and apparatus which is particularly applicable to a first space having treated air requirements corresponding to those in a dining area in a restaurant or the like and a second space having treated air requirements corresponding to those in a cooking area of the like; and to provide such a method and apparatus which is efficient and effective in operation, is relatively simple to install and may be varied to provide different embodiments for different areas or spaces.